| 摘要 |
The filter, having a length N and a decimation factor q, comprises a first (4) and a second (10) digital delay line, both consisting of a cascade arrangement of a number of auxiliary delay lines (4.1, 4.2, 10.1, 10.2) each having a time delay qT. An individual distribution line (5) is connected to the input of each of the delay lines as well as to the output of each of the auxiliary delay lines. Digital input signal components (x (n)) occurring with a period T are applied to the input of the first digital delay line (4) and each auxiliary delay line contains q of these components. These two delay lines (4, 10) are coupled to one another by means of a sequence reversing device (6) which comprises a store (7) having a capacity of q signal components. This reversing device (6) applies, in the next control interval, q input signal components, produced in a given control interval of length qT by the first delay line (4), in reversed order to the second delay line (10). Every two distribution lines which are arranged symmetrically relative to a symmetry line being connected to inputs of an adder device (11) the output of which is connected to an input of an accumulation device (13) via a multiplying device (12). A sequence of filter coefficients being applied to the multiplying device (18). The accumulation device (13) now produces the sum (14) of all products formed in a control interval. |
